I know this isnt an ISA related question but there has been discussion about it. I have downloaded and installed SP 1 on W2k3 server multiple times using the same source files. I have one DC that continually generates the same error when I try to install it. "Setup could not verify the integrity of Update.inf. Make sure the cryptographic service is running on this computer" I have checked and rechecked and nothing is out of place. I have restarted the service and the computer as well. Has anyone else had problems installing this?